- Gas Detection Equipment in the Drinks Industry
- Gas Detection Equipment in the Gas & Oil Industry
- Gas Detection Equipment in the Household
- Gas Detection Equipment in the Commercial Field
- Gas Detection Equipment in the Metallurgical Industry
- Gas Detection Equipment in the Energy Storage Industry
- Gas Detection Equipment in the Pharmaceutical Industry
Equipment Selection and Layout: Technical Considerations for Harsh Environments
Metallurgical environments pose extreme challenges—high temperatures (up to 1000°C+), high dust levels (e.g., sintered ore dust), strong corrosion (e.g., H₂S in acidic gases), and electromagnetic interference (e.g., near electric furnaces). Equipment selection and layout must adhere to the following principles:
(1) Selection by Monitored Gas Type
| Gas Type | Recommended Detector Type | Principle and Application | Key Parameters |
| Carbon Monoxide (CO) | Electrochemical, Infrared | Electrochemical (precise, detection limit ≤10 ppm, for high-accuracy monitoring); Infrared (dust-resistant, for long-term use in high-temperature blast furnace gas) | Electrochemical: Range 0–1000 ppm (or higher), response time ≤30 sec; Infrared: Range 0–100% VOL |
| Hydrogen (H₂) | Thermal Conductivity, Semiconductor | Thermal conductivity (leveraging hydrogen’s high thermal conductivity, anti-interference, suitable for low-concentration monitoring); Semiconductor (low-cost but susceptible to cross-interference) | Thermal conductivity: Detection limit ≤1% LEL (~0.5% VOL); Semiconductor: Requires regular calibration |
| Methane (CH₄) | Catalytic Combustion, Infrared | Catalytic combustion (cost-effective for low-concentration CH₄); Infrared (silicon-poisoning resistant, for long-term monitoring in blast furnace gas) | Catalytic combustion: Range 0–100% LEL; Infrared: Range 0–50% VOL |
| Hydrogen Sulfide (H₂S) | Electrochemical (Anti-Interference Type) | Detection limit ≤1 ppm, corrosion-resistant sensor materials (e.g., 316L stainless steel or special coatings) | Range 0–100 ppm, response time ≤60 sec |
| Oxygen (O₂) | Electrochemical | Range 0–25% VOL (or 0–30% VOL), alarm threshold ≤19.5% VOL (oxygen deficiency warning) | Accuracy ±2% FS (full-scale error) |
| Multi-Gas Composite | Multi-Gas Detectors (CO+H₂+CH₄+O₂, etc.) | Suitable for high-risk areas requiring simultaneous monitoring of multiple gases (e.g., blast furnace tuyere platforms, gas recovery systems) | Independent alarm thresholds, flexible interlocks |
(2) Adaptation to Environmental Conditions
● High-Temperature Environments (e.g., Blast Furnace Top, Converter Areas): Use high-temperature detectors(operating temperature ≥200°C, some models up to 800°C) or cooling protection sleeves (e.g., air/water-cooled jackets) to reduce sensor exposure.
● High-Dust Environments (e.g., Sintering Machines, Dust Collector Inlets): Employ dust-proof sampling probes(with reverse-blowing function to clear dust periodically) or extractive detectors (drawing gas to an analysis chamber away from dust).
● Corrosive Environments (e.g., Sulfur-Containing Gas Areas): Sensor materials should be 316L stainless steel, Hastelloy, or PTFE (polytetrafluoroethylene)-coatedto resist corrosion from H₂S, SO₂, and other corrosive gases.
● Electromagnetic Interference Zones (e.g., Near Electric Furnaces, Variable Frequency Equipment): Choose EMI-resistant detectors(shielded cables, grounded metal housings) to ensure stable signal transmission.
(3) Layout Principles: Covering High-Risk Leakage Points
● Fixed Detectors (Mainstream Choice): Installed at fixed locations prone to gas leaks(e.g., pipeline valves, flange connections, 0.3–0.6 meters below gas pipelines (where CO/H₂ and other slightly lighter/heavier gases accumulate), inside sealed equipment (e.g., dust collectors, furnace covers)).
● Key Area Coverage:
1) Blast Furnace Top Platform: Install CO/H₂detectors near pipeline interfaces, tuyere areas (spacing ≤5 meters);
2) Converter Gas Recovery System: Place CO/CH₄detectors at gas holder inlets, valve rooms, and dust removal pipeline inlets;
3) Gas Holders: Layered detectors at the top (CH₄accumulation zone), middle (mixed zone), and bottom (CO settling zone);
4) Rolling Mill Heating Furnaces: Install CO/CH₄detectors at furnace seals, fuel pipeline (natural gas/blast furnace gas) interfaces, and flue gas inlet pipelines.
● Portable Detectors (Supplementary Tool): Used by inspectors entering confined spaces (e.g., dust collector interiors, underground gas pipelines) for pre-entry checks or emergency leak investigations.